Regex use - compile error

[scippio@…]

Hi, I have problem in my little test program:

	std::string decoded = "this is standart string with username=\"myusername\" etc. ";
	
	static const boost::regex regUsername("username=\"(.*)\"");
	boost::cmatch matches;
	std::string::const_iterator begin;
	begin = decoded.begin();
	
	while(boost::regex_search(begin, decoded.end(), matches, regUsername)){
		std::string text(matches[1].first, matches[1].second);
		std::cout << "OUTPUT: " << text << std::endl;
		begin = matches[1].second;
	}

compile error:

ccache g++ -o test.o -c -O2 -Wno-deprecated -Wall -Iinc test.cpp
test.cpp: In member function ‘void authorization()’:
test.cpp:211: error: no matching function for call to ‘regex_search(__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >&, __gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::cmatch&, const boost::regex&)’
test.cpp:214: error: no match for ‘operator=’ in ‘begin = ((const boost::sub_match<const char*>*)matches.boost::match_results<BidiIterator, Allocator>::operator[] [with BidiIterator = const char*, Allocator = std::allocator<boost::sub_match<const char*> >](1))->boost::sub_match<const char*>::<anonymous>.std::pair<const char*, const char*>::second’
/usr/lib/gcc/i686-pc-linux-gnu/4.4.0/../../../../include/c++/4.4.0/bits/stl_iterator.h:669: note: candidates are: __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >& __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >::operator=(const __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >&)
scons: *** [test.o] Error 1

[Steven Watanabe]

The two iterators have different types. You're passing a std::string::const_iterator as the first argument to regex_search and a std::string::iterator as the second argument.

[scippio@…]

I try both iterators std::string::const_iterator and std::string::iterator and compile errors is still there.

try this:

std::string::const_iterator begin;
begin = decoded.begin();
std::string::const_iterator end;
end = decoded.end();

or this:

std::string::iterator begin;
begin = decoded.begin();
std::string::iterator end;
end = decoded.end();

errors are same..

[anonymous]

Steven was almost correct: you're using cmatch which is a typedef for match_results<const char*>, but then passing string iterators to the function. Use the typedef boost::smatch with string iterators.

HTH, John.

[scippio@…]

You have true... sorry for stupid ticket :(